Western Ontario Shoulder Instability Index (WOSI)

The Western Ontario Shoulder Instability Index (WOSI) is a 21-item, shoulder-specific, self-administered questionnaire measuring functional disability in patients with shoulder instability.

The WOSI comprises four sub-scales:

• Physical Symptoms (10 items, 0-1000 points)

• Sports/Recreation/Work (4 items, 0-400 points)

• Lifestyle (3 items, 0-300 points)

• Emotion (3 items, 0-300 points)

The WOSI yields a total score of 0-2100 points with higher scores indicating greater disability. Each item is rated 0-100% by the patient.

The instrument has demonstrated excellent reliability, validity, and responsiveness in evaluating treatment outcomes and functional capacity in shoulder instability populations, making it valuable for baseline assessment, progress monitoring, and comparative effectiveness research.

Original Literature:

Kirkley, Alexandra, et al. “The development and evaluation of a disease-specific quality of life measurement tool for shoulder instability.” The American Journal of Sports Medicine 26.6 (1998): 764-772.

Additional Literature:

Salomonsson, Björn, et al. “The Western Ontario Shoulder Instability Index (WOSI): validity, reliability, and responsiveness retested with a Swedish translation.” Acta orthopaedica 80.2 (2009): 233-238.

Angst, Felix, et al. “Measures of adult shoulder function: Disabilities of the arm, shoulder, and hand questionnaire (DASH) and its short version (QuickDASH), shoulder pain and disability index (SPADI), American shoulder and elbow surgeons (ASES) society standardized shoulder assessment form, constant (Murley) score (CS), simple shoulder test (SST), oxford shoulder score (OSS), shoulder disability questionnaire (SDQ), and Western Ontario shoulder instability index (WOSI).” Arthritis care & research 63.S11 (2011).

• Assess your shoulder symptoms and functional limitations over the past week.

• Rate your experience on a 0-100% scale, where 0% means no problem and 100% means the worst possible problem.

• Responses are reported as whole number percentages.